Some Considerations on the Allocation of Reliability and Maintainability for Marine Engine System due to Failure Field Data

Abstract

The more redundant system of m-multi engines is able to give the higher availability to total ship but unavoidable to require the more manpower to maintenance crews.
The following equation as a function of maintenance intensity ρ_i is led to the redundant system of m-multi repairable engines according to the combination of three kinds of trouble conditions of each engine; (ρ₀+ρ_w+ρ_z)^m=ρ^m₀+Σ^m_{l=1 m}C_lρ^m-l₀ρ^l_w+Σ^m_{q=1 m}C_q(ρ₀+ρ_w)^m-qρ^q_z=1l, q≤m, ρ_i= λ_i/μ_i (i=0, w, z) where λ_i; failure rate, μ_i; maintenance rate of maintenance level of S_i, subscript i as follows;
z; emergency failure (x; stoppage of engine, y; slow down of engine)
w; non-emergency failure,
0; normal operation
There were obtained some useful informations concerning the allocation of reliability and maintainability and utilization of its maintenance crew due to a lot of failure field data of marine engine. Furthermore the above equation was confirmed by the single markov model for redundant system of marine repairable engines in appendix.